1. Field of the Invention
The present invention relates to a method of controlling a communication terminal and a communication terminal apparatus for use with a radio telephone apparatus called a portable telephone terminal and a communication system using such communication terminal apparatus, for example. More specifically, this invention relates to a method of controlling the execution of the functions in a communication terminal having one or more functions different from a communication function, a communication terminal apparatus and a communication system using such communication terminal.
2. Description of the Related Art
Heretofore, there have been proposed various combined terminals which are communication terminal apparatus for use as radio telephone apparatus having other functions different from a telephone function combined therewith. Since radio telephone apparatus are generally designed to be compact in size so that users can usually carry them when in use, there are radio telephone apparatus having a radio telephone function and extra functions such as a clock function and a schedule managing function to display necessary information such as time information and schedule information on a display device of a terminal apparatus.
As a storage capacity of a semiconductor memory is increasing and an audio data compression technology is improving in recent years, a memory incorporated within a memory card becomes able to store audio data of approximately several 10 s of minutes to several hours, for example. Small reproducing apparatus having this memory card as a recording medium (storage medium) and a headphone are now commercially available as audio players capable of reproducing audio data or sounds so that users can listen to reproduced audio data or sounds through the headphone.
There is proposed a highly-capable combined terminal having an audio reproducing apparatus incorporated within a portable terminal apparatus. Because the portable telephone terminal incorporates the audio reproducing apparatus using the above memory as the recording medium, when the portable telephone terminal is not in use as a telephone for making a telephone conversation, a user can listen to audio data or sounds reproduced through the headphone attached to the portable telephone terminal. With this arrangement, services of portable telephone terminals can be expanded.
The above portable telephone terminal can download audio data on the memory card attached thereon from a center through a radio telephone network line, for example, and can store the audio data thus downloaded in the memory card. Therefore, users can get audio data with ease, which is very convenient for users.
A distribution service for distributing audio data to the above portable telephone terminal incorporating the audio reproducing apparatus may be a pay distribution service. Since it has been customary that such pay distribution service is under control of a telephone company for operating a radio telephone system, the telephone company may collect charges for the pay distribution services from users. Even when the audio data distribution service is free, the telephone company usually serves the free audio distribution to the users of the portable telephone terminals as one of additional services. Therefore, with respect to the above free audio distribution service, it is desirable that only those who had contracted with the telephone company should be served.
Further, since the audio reproducing apparatus of the portable telephone terminal is essentially the portable telephone terminal, the telephone company may charge for the audio data distribution service each time a user reproduces audio data by the portable telephone terminal. Specifically, when audio data that has been downloaded on the portable telephone terminal is reproduced, a real time accounting is made possible by transmitting data indicating the reproduction of audio data to the center of the radio telephone company through the telephone network line. In this manner, when the portable telephone terminal incorporates the audio reproducing apparatus, the audio data distribution service becomes possible under the condition that a copyright concerning the reproduction of music can be protected reliably.
On the other hand, since it is customary that the telephone company sells the portable telephone terminal incorporating the audio reproducing apparatus to the contractors of the telephone network line, even when a user who is a contractor of the telephone network line has canceled the contract of the radio telephone network line, the portable telephone terminal itself still remains for the user. If the portable telephone terminal the contract of which has been canceled is used as the audio reproducing apparatus, then a user become able to freely listen to downloaded audio data reproduced from the audio reproducing apparatus out of control of the telephone company, which is undesirable from a copyright protection standpoint.
There are places and situations in which a use of the portable telephone terminals should preferably be prohibited. In such places and situation, users are usually requested to switch off the portable telephone terminal and a use of the terminal should be prohibited. In hospitals, for example, in order to protect medical equipment from malfunctioning due to radio waves from the portable telephone terminals, it is recommended that users should switch off the portable telephone terminals. This applies for the portable telephone terminal incorporating the audio reproducing apparatus as well so that users are requested to switch off the portable telephone terminals in the hospital. However, at the same time the power-switch of the portable telephone terminal is turned off, the audio reproducing function assembled into the portable telephone terminal also is de-energized so that a user cannot listen to a piece of music reproduced by the audio reproducing function incorporated in the portable telephone terminal through the headphone attached to the portable telephone terminal in the waiting room of the hospital, for example.
While the problem encountered with the portable telephone terminal incorporating the audio reproducing apparatus has been described so far, there arises a similar problem when a similar communication terminal incorporates other functions which are not directly related to radio communications.